Which of the following statements about catalysts is correct? MCQ with Answer and Explanation

Which of the following statements about catalysts is correct?
A. They are consumed in the reaction
B. They are always solid
C. They lower the activation energy of the reaction
D. They change the equilibrium constant
Answer: Option C
Solution (By JKSSB Mock Tests)
Catalysts provide an alternative pathway with lower activation energy, increasing reaction rate without being consumed. They do not affect equilibrium constant or thermodynamic parameters (ΔH, ΔS). They can be solid (heterogeneous), liquid, or gas. Enzymes are liquid-phase catalysts. A catalyst does not change the position of equilibrium, only speeds up attainment.

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Which enzyme converts glucose into ethanol?
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B. Maltase
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Correct Answer: Option A


Explanation:
Zymase, a complex of enzymes from yeast, catalyzes fermentation: C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂. Invertase hydrolyzes sucrose; urease hydrolyzes urea; maltase converts maltose to glucose.

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Question #2
Assertion (A): Radioactive decay is a nuclear process. Reason (R): It involves changes in the nucleus of an atom.
A. A is true but R is false.
B. Both A and R are true and R is the correct explanation of A.
C. A is false but R is true.
D. Both A and R are true but R is NOT the correct explanation of A.

Correct Answer: Option B


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Correct Answer: Option C


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